A healthy intervertebral disc facilitates motion between pairs of vertebrae while absorbing and distributing shocks. The disc is composed of two parts: a soft central core (the nucleus pulposus) that bears the majority of the load, and a tough outer ring (the annulus fibrosis) that holds and stabilizes the core material.
As the natural aging process progresses, the disc may dehydrate and degenerate, adversely affecting its ability to adequately cushion and support the vertebral bodies. This natural desiccation, which in its more advanced state is often referred to as “black disc” because of the disc's dehydrated appearance on Magnetic Resonance Imaging [MRI], can cause discomfort to the patient as the vertebrae to come closer together—compressing the spinal nerves and causing pain.
Techniques for addressing degenerative disc disease have heretofore relied primarily on disc replacement methods. In cases in which a dehydrated and/or degenerating disc was augmented before disc replacement was required, the augmentation materials have primarily been synthetic devices that expand, are inflated, or deploy expanding elements when implanted into the disc.
A need therefore exists for materials and methods effective for augmenting intervertebral discs with natural materials. The present invention addresses that need.